Logo
FULL SITE MENU

Listen to your motor

V

Vinh

Regular Contributor
I have a 16.5' CC with an 86 Yamaha 2 stroke. I cleaned the gas tank, carb, fuel filter 4 months ago. The engine runs good until a few nights ago that it idled very low, even after it warmed up. Sometimes it just shut off by itself even at higher RPM. I knew this is not normal. Today I open the carbs and clean them and found signs of water in the bowls. So I clean out the carbs. I open up the fuel filter at the engine and there is 1/4 of the cup filled with water. I removed the water separator and saw rusts and milky stuff inside the filter. I pour the gas out and sure enough 1/4 of the liquid was water. I replaced the water separator and it runs perfect again. The point is listen to your motor. If it shows sign of abnormal then check the fuel and clean out everything fuel related.

PS. I just remembered that a month ago I ran the gas tank all the way down. This probably caused the motor to suck the water out from the bottom of the gas tank. Even though I cleaned out the gas tank a few months ago I think the water went back into the gas tank via the vent hole. I check the vent hole on my boat and it's wide open. If any wave hits it the water will enter the tank. I am putting a cover over the top of it and clean out the gas tank one more time.
 
Last edited:
All fuel pickup tubes go to the bottom of the tank. If there is water in your fuel, the pickup tube will be pulling it in full or almost empty.

Check your fuel tank fill cap o-ring if you have a screw in cap. Replace the vent on your fuel tank. Make sure to get a quality one.

Rain water will fill your tank over night if your vent is turned up or your fill cap is not sealing properly.
 
So I went out fishing last night and the motor was running fine for 10 mins and then shuts off. Couldn't start after that. I knew it was water in the fuel. So I looked thru the clear fuel filter I have in the line and yup saw some water there. So I remove the drain plugs for the carbs and drain all the fuel out. I removed the fuel filter at the engine and it was filled with water. I dump the water out. I remove the inlet line to the fuel pump and put it into a clear bottle. Pump the fuel into the bottle until the clear fuel filter shows no sign of water. I look at the bottle and almost half of it was water. Plug the fuel line back up and pump fuel into the carbs and it ran good again. I alsodisconnect the vent hose and left it inside the boat. Will have to empty out the fuel/water seperator today.
 
If you have that much water in the tank, you need to raise the bow of the boat up some how, remove the fuel sender and suck all the water off the bottom of the tank. Or the next time you push the throttle up and the bow of the boat comes up you will fill the fuel system with water again.
 
Back
Top